Clinical Effect Of Tumor-type Joint Prosthesis Replacement On The Treatment Of Periarticular Osteosarcoma

Objective:To evaluate the clinical efficacy of tumor-type joint prosthesis replacement for the treatment of osteosarcoma around the knee.Methods:Follow-up of 48 cases of knee osteosarcoma patients diagnosed and performed with neoadjuvant chemotherapy and tumor prosthesis replacement surgery at the First Affiliated Hospital and Cancer Hospital of Guangxi Medical University from 2007 to 2017.According to the tumor location,they were divided into two groups: the distal femur group and the proximal humerus group,of which 30 were in the distal femur group and 18 were in the proximal humerus group.The average follow-up time was 32.5months(6-106 months).Follow-up included: survival of patients,postoperative limb function and artificial prosthesis.Knee functional assessment was performed using the MSTS scoring system and knee flexion range 6 monthsafter surgery.Kaplan-Meier survival curves were used to evaluate postoperative2-year survival rate and 2-year prosthesis survival rate,and to analyze the incidence of postoperative prosthesis complications.Results:Kaplan-Meier method was used to establish survival curves for the survival time of patients with distal femur and proximal humerus groups.The two-year survival rates of the two groups were 75.0% and 66.7%,respectively(P=0.737).There was no statistical difference in postoperative survival at 2years.MSTS functional scores(6 months postoperatively)were obtained in 29 survivors who had completed follow-up.The distal femur was 25.3±2.4,and the proximal tibial was 23.3±3.4(P=0.091),indicating that the distal femur was The posterior function was better than the proximal humerus group,but there was no statistical difference between the two groups.Six months after operation,the degree of knee joint activity was 93.5°±6.3° in the distal femur group and87.9°±10.8° in the proximal humerus group(P=0.088).This indicated that the range of knee flexion in the distal femur group was better than that in the proximal humerus.Group,but no statistical difference between the two groups.Kaplan-Meier method was used to make the survival curve of the prosthesis survival time in patients with distal femur and proximal humerus.The two-year survival rate of the two groups was 70.0% and 58.3%,respectively(P=0.620).There was no statistical difference in the survival rate of the prosthesis between the two groups after 2 years.The univariate analysis of the factors that may affect the patient's 2-year survival rate of the prosthesis revealed that BMI,tumor size,and pathological fractures were risk factors for the survival of the prosthesis,and the patient's gender,first consultation age,tumor site,and Enneking Stages are not related factors that affect the survival of the patient's prosthesis.The incidence of all kinds of postoperative complications was 10.4%(5/48).Prosthesis loosening was found in 1 patient in the distal femur group and1 patient was infected around the prosthesis.In the proximal humerus group,2patients had periprosthetic infection,1 case around the fracture of the prosthesis.Conclusion: In the present study,patients with periprosthetic osteosarcoma undergoing tumor-type joint prosthesis replacement have a good oncological prognosis and satisfactory postoperative limb function in the short term.The range of knee joint function and flexion in the distal femur group was better than that in the proximal humerus group,There was no statistical difference between the two groups.There is a certain proportion of complications after artificial tumor prosthesis replacement,Pathological fractures?tumor size?and patient BMI were risk factors that affected the survival of the prosthesis,tumor site?gender? first consultation age and Enneking stage had no significant effect on the survival of the prosthesis.